#include <gtest/gtest.h>

#include <algorithm>
#include <filesystem>
#include <fstream>
#include <stdexcept>
#include <string>

#include "fesa/io/abaqus/domain_mapper.h"
#include "fesa/io/abaqus/input_reader.h"

namespace {

class TemporaryInputFile {
 public:
  TemporaryInputFile(const std::string& stem, const std::string& content)
      : path_{std::filesystem::temp_directory_path() /
              ("fesa-eigen-domain-" + stem + ".inp")} {
    std::ofstream stream{path_, std::ios::binary | std::ios::trunc};
    stream.write(content.data(), static_cast<std::streamsize>(content.size()));
    if (!stream) {
      throw std::runtime_error{"Unable to create eigen domain fixture."};
    }
  }

  ~TemporaryInputFile() {
    std::error_code error;
    std::filesystem::remove(path_, error);
  }

  const std::filesystem::path& Path() const noexcept { return path_; }

 private:
  std::filesystem::path path_;
};

fesa::Result<fesa::Domain> MapText(const std::string& stem,
                                   const std::string& content) {
  const TemporaryInputFile input{stem, content};
  auto parsed = fesa::AbaqusInputReader{}.Read(input.Path());
  if (!parsed.HasValue()) {
    return fesa::Result<fesa::Domain>::Failure(parsed.GetStatus());
  }
  return fesa::AbaqusDomainMapper{}.Map(parsed.Value());
}

std::string EigenDeck(const std::string& density = "2700.,",
                      const std::string& frequency = "10, , , , ,") {
  return R"inp(*Part, name=ShellPart
*Node
1, 0., 0., 0.
2, 1., 0., 0.
3, 1., 1., 0.
4, 0., 1., 0.
*Element, type=S4R
1, 1, 2, 3, 4
*Elset, elset=ShellSet
1
*Shell Section, elset=ShellSet, material=Steel
0.5, 5
*End Part
*Assembly, name=Assembly
*Instance, name=Shell-1, part=ShellPart
*End Instance
*Nset, nset=Root, instance=Shell-1
1
*End Assembly
*Material, name=Steel
*Density
)inp" + density +
         R"inp(
*Elastic
2.1e11, 0.3
*Boundary
Root, 1, 6
*Step, name=Step-2, nlgeom=NO, perturbation
*Frequency, eigensolver=Lanczos, sim, acoustic coupling=on, normalization=mass
)inp" + frequency +
         R"inp(
*Restart, write, frequency=0
*Output, field
*Node Output, variable=PRESELECT
*Output, history
*Energy Output, variable=ALL
*End Step
)inp";
}

const fesa::Diagnostic* FindDiagnostic(const fesa::Status& status,
                                       const std::string& code) {
  for (const auto& diagnostic : status.Diagnostics()) {
    if (diagnostic.code == code) {
      return &diagnostic;
    }
  }
  return nullptr;
}

TEST(EigenDomainMapping, PreservesFrequencyDensityAndSourceStepIdentity) {
  auto result = MapText("accepted", EigenDeck());
  ASSERT_TRUE(result.HasValue());
  const fesa::Domain& domain = result.Value();

  ASSERT_EQ(domain.Densities().size(), 1U);
  EXPECT_EQ(domain.Densities()[0].material_index, fesa::EntityIndex{0U});
  EXPECT_DOUBLE_EQ(domain.Densities()[0].rho, 2700.0);
  ASSERT_NE(domain.Frequency(), nullptr);
  EXPECT_EQ(domain.Frequency()->source_step_name_raw, "Step-2");
  EXPECT_EQ(domain.Frequency()->source_step_name_canonical, "STEP-2");
  EXPECT_EQ(domain.Frequency()->requested_mode_count, 10);
  EXPECT_TRUE(domain.Frequency()->perturbation_explicit);
  EXPECT_TRUE(domain.Frequency()->sim_explicit);
  ASSERT_EQ(domain.Steps().Size(), 1U);
  EXPECT_TRUE(domain.Steps()[0U].IsFrequency());
  EXPECT_EQ(domain.Steps()[0U].Frequency(), domain.Frequency());
  EXPECT_EQ(domain.Steps()[0U].Name(), "Step-2");
  ASSERT_EQ(domain.Steps()[0U].BoundaryConditions().size(), 6U);
  EXPECT_TRUE(domain.Steps()[0U].Loads().empty());
}

TEST(EigenDomainMapping, RejectsInvalidDensityAndFrequencySlots) {
  auto density = MapText("bad-density", EigenDeck("2700., 1."));
  ASSERT_FALSE(density.HasValue());
  EXPECT_NE(FindDiagnostic(density.GetStatus(), "invalid-density-data"),
            nullptr);

  auto slots = MapText("bad-slots", EigenDeck("2700.,", "10, 0"));
  ASSERT_FALSE(slots.HasValue());
  EXPECT_NE(FindDiagnostic(slots.GetStatus(), "invalid-frequency-data"),
            nullptr);
}

TEST(EigenDomainMapping, RejectsMissingActiveDensityAndNonzeroBoundary) {
  std::string missing_deck = EigenDeck();
  const std::string density_block = "*Density\n2700.,\n";
  const std::size_t density_location = missing_deck.find(density_block);
  ASSERT_NE(density_location, std::string::npos);
  missing_deck.erase(density_location, density_block.size());
  auto missing = MapText("missing-density", missing_deck);
  ASSERT_FALSE(missing.HasValue());
  EXPECT_NE(FindDiagnostic(missing.GetStatus(), "missing-material-density"),
            nullptr);

  std::string nonzero = EigenDeck();
  const std::string source = "Root, 1, 6";
  const std::size_t location = nonzero.rfind(source);
  ASSERT_NE(location, std::string::npos);
  nonzero.replace(location, source.size(), "Root, 1, 6, 1.");
  auto boundary = MapText("nonzero-boundary", nonzero);
  ASSERT_FALSE(boundary.HasValue());
  EXPECT_NE(FindDiagnostic(boundary.GetStatus(), "unsupported-eigen-boundary"),
            nullptr);
}

TEST(EigenDomainMapping, RejectsMixedProceduresInvalidOutputAndSurface) {
  std::string mixed = EigenDeck();
  mixed.insert(mixed.find("*Restart"), "*Static\n0.1, 1., 0.01, 1.\n");
  auto mixed_result = MapText("mixed-procedures", mixed);
  ASSERT_FALSE(mixed_result.HasValue());
  EXPECT_NE(FindDiagnostic(mixed_result.GetStatus(),
                           "unsupported-analysis-procedure"),
            nullptr);

  auto wrong_output = MapText(
      "wrong-output",
      EigenDeck().replace(EigenDeck().find("*Output, field\n*Node Output"),
                          std::string{"*Output, field\n*Node Output"}.size(),
                          "*Output, history\n*Node Output"));
  ASSERT_FALSE(wrong_output.HasValue());
  EXPECT_NE(FindDiagnostic(wrong_output.GetStatus(), "unsupported-keyword"),
            nullptr);

  std::string surface = EigenDeck();
  surface.insert(surface.find("*Material"),
                 "*Surface, name=Face, type=ELEMENT\n");
  auto surface_result = MapText("surface", surface);
  ASSERT_FALSE(surface_result.HasValue());
}

TEST(EigenDomainMapping, RejectsInvalidPreprintAndAcceptsStrictNoOp) {
  const std::string preprint =
      "*Preprint, echo=NO, model=NO, history=NO, contact=NO\n";
  auto accepted = MapText("preprint", preprint + EigenDeck());
  ASSERT_TRUE(accepted.HasValue());
  const auto warning = std::find_if(accepted.Value().Warnings().begin(),
                                    accepted.Value().Warnings().end(),
                                    [](const fesa::Diagnostic& diagnostic) {
                                      return diagnostic.keyword == "PREPRINT";
                                    });
  ASSERT_NE(warning, accepted.Value().Warnings().end());
  EXPECT_EQ(warning->message, "mandatory-eigen-output-unchanged");

  auto rejected =
      MapText("bad-preprint", "*Preprint, echo=YES\n" + EigenDeck());
  ASSERT_FALSE(rejected.HasValue());
  EXPECT_NE(FindDiagnostic(rejected.GetStatus(), "unsupported-keyword"),
            nullptr);

  auto missing_parameters =
      MapText("bare-preprint", "*Preprint\n" + EigenDeck());
  ASSERT_FALSE(missing_parameters.HasValue());
  EXPECT_NE(
      FindDiagnostic(missing_parameters.GetStatus(), "unsupported-keyword"),
      nullptr);
}

}  // namespace